Battery performance is an important factor in the operation and reliability of consumer devices, apparatus and vehicles. Battery testing, particularly that conducted with batteries incorporating advanced technology, is an important stage of the battery development process. Typically, battery testing procedures require battery exercising equipment to charge and discharge battery cells in accordance with predetermined test profiles designed to simulate various operating conditions. The testing apparatus measures and records cell characteristics during the charging exercises so that battery performance can be evaluated.
Unfortunately, problems at the devices under test and/or faults at the testing equipment can occur during the battery testing process. Typically, an operator can specify test constraints for the cells being tested, for example, an operator can designate upper and/or lower voltage and temperature limits. Should cell characteristics violate the test constraints, exercising of the battery cells can be terminated. However, testing equipment can malfunction, sensors or probes may fail, and processing errors can occur. In such cases, the test equipment may fail to detect that cell environmental characteristics are beyond test limit specifications. Consequently, testing procedures are conducted under human supervision so that an operator can intervene if something goes awry.
Even with sophisticated multi-channel testing equipment, battery cell testing can be a lengthy and time-consuming process. For example, testing of electrochemical cells for a hybrid electric vehicle (HEV) high-voltage battery can require testing 24 hours/day for multiple days, far exceeding the 8-hour work day of a typical test operator. As a result, a test is often commenced at the beginning of an operator work shift, interrupted when a shift is completed, and then resumed on a subsequent shift. Performed at this type of pace, a single test can require weeks, or perhaps months to complete. In addition to prolonging the length of time necessary to conduct the test, intermittent starting and stopping of the charging and discharging processes can introduce rest periods and transient effects that can skew results and lead to inaccurate conclusions regarding cell and battery performance.